In response to the problems such as unclear particle size, microscopic morphology, anion and cation components, accumulation patterns and influencing factors of insulator contamination in the arid regions of the west, taking Ningxia as an example, samples of contamination were collected from the desert interior, the desert edge and the industrial areas adjacent to the desert edge, and their physical and chemical properties were analyzed; based on the analysis results, a typical porcelain insulator contamination simulation model was established to simulate and study the influence of different wind speeds, particle sizes, contamination components and voltage types on the contamination accumulation patterns of insulators on the surface. The results showed that the average contamination particle size of insulators on transmission lines in arid regions is less than 30 μm and is prone to deposit on the insulator surface. The main cations in the contamination include Mg2+, Al3+, Fe3+, etc., and the main anions include Cl−, NO3−, F−, etc. The contamination accumulation pattern of insulators in the AC field shows a “M” shape distribution, while that in the DC field shows a “U” shape distribution. Under the same conditions, the contamination attachment rate of insulators in the DC field is 2.9 times that of the AC field.